This invention relates to metal roof construction.
Where a metal panel roof is interrupted by an opening for a skylight or the like, the perimeter of the opening is framed with "closure" members to reinforce the opening and to provide a weather seal around the opening. The closure member may be made from "Z"-section channel stock.
Panel closures are usually installed by one of the following methods:
1. Factory formed panel closures, cut to about panel length at the factory, are fitted to the panel seam shape and then each individual closure is installed. Problems associated with this method are (a) the cost of tooling to manufacture each individual closure part, (b) the fact that one standard closure part will not work on hip conditions (e.g., where diagonal cuts varying in length are required), and (c) the finished installation is typically not as with straight as when a longer closure that spans numerous panels (i.e., a closure ten or twelve feet long). This method requires more parts, making the system more time consuming to install. PA1 2. Nominal length closures (ten or twelve feet long) are field cut to fit across a panel, and tabs are field formed to the panel shape; then each individual panel closure is installed. The problem with this method is high labor cost resulting from the time needed to hand cut and then form each panel. Like the previous method, the finished installation is typically not as straight as possible. Also, the fit-up of the field notching is usually not very accurate. PA1 3. Nominal length closures are field notched with hand snips to fit over several panel seams and then the full length piece is installed. The principal difficulty with this method is that of cutting the required shape around each panel corrugation with hand snips. Depending on the panel shape, it may be impossible to notch the closure member only with snips. Drilling or punching or chiseling may be required. Inaccuracies in field cutting may lead to leakage, and in any event, custom notching by hand is time consuming.
The proposed new method permits the use of long ten or twelve foot "Z"-section closures with the accuracy of a factory cut notch, but the notching can be performed in the field with a special hand tool. This tool punches out the corrugation shape from the vertical web of the closure, where it is difficult to snip by hand, but permits hand snipping the bottom flange at any angle desired, so that closures can be installed at non-perpendicular angles to the seams, for example on hip roofs.